Vitamin D and depressive symptoms in children with cystic fibrosis.

BACKGROUND

Vitamin D deficiency has been hypothesized to play a role in the development of depression. Hypovitaminosis D is almost universal in patients with cystic fibrosis (CF). No studies to date have explored associations between serum concentrations of 25-hydroxyvitamin D (25(OH)D), a standard measure of vitamin D, and depression in patients with CF.

OBJECTIVE

This pilot study aimed to explore the relationship between 25(OH)D and the presence of depressive symptoms among youth with CF.

METHODS

A cross-sectional study was conducted at an ambulatory Cystic Fibrosis Center clinic. Serum 25(OH)D and Children's Depression Inventory (CDI) scores were analyzed from 38 youths with CF ages 7-17 years. Child depressive symptoms were measured using the CDI, with scores above 12 indicating a significant level of depressive symptoms. Serum 25(OH)D concentration were measured using the liaison 25 OH vitamin D assay. Insufficient vitamin D status was defined as a circulating 25(OH)D concentration less than 30 ng/mL.

RESULTS

Insufficient vitamin D levels were found in 59% of patients; 28% of patients had significant levels of depressive symptoms on the CDI (scores >12). Serum 25(OH)D was negatively associated with CDI scores (r = -0.55; p < 0.001), and the group of patients with insufficient 25(OH)D levels indeed reported significantly more depressive symptoms (t = 4.26; p < 0.001).

CONCLUSIONS

25(OH)D insufficiency was associated with depressive symptoms in this cohort of youth with CF. Future rigorous studies investigating vitamin D and depression in CF are warranted with larger sample sizes using confirmatory methods to diagnose depressive disorders.